Euphorbia plant named ‘Vanilla Swirl’

ABSTRACT

A new cultivar of Euphorbia named ‘Vanilla Swirl’ that is distinguished by a compact rounded habit, variegated foliage exhibiting white margins and green centers, and bright red stems that fade to pink. In combination these traits set ‘Vanilla Swirl’ apart from all other existing varieties of Euphorbia known to the inventor.

Genus: Euphorbia.

Species: characias.

Denomination: ‘Vanilla Swirl’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of spurge,a hardy perennial that is grown for its unique foliage and its use as anornamental landscape plant. The new invention is known botanically asEuphorbia characias and will be referred to hereinafter by the cultivarname ‘Vanilla Swirl’.

‘Vanilla Swirl’ was discovered by the inventor in 1998 in Bury St.Dorset, United Kingdom as a self-set seedling found in a cultivated areaof the inventor's garden beneath a small group of Euphorbia characias.The female or seed parent is presumed to be Euphorbia characias and themale or pollen parent is presumed to be Euphorbia characias. ‘VanillaSwirl’ was selected by the inventor for its variegated leaves thatexhibit green centers and irregular cream-white margins, compact roundedgrowth habit, bright red stems in spring that fade to pink by summer andconsistent variegation of the foliage without reversion to green. Rarelyoccurring flowers are held on terminal stems and born axial to the leafjoints with two cyathia cupped by two basally fused floral leaves, alsocalled involucres. The margins of the leaves are whitest in spring andbecome cream-white in summer.

The closest comparison plant is Euphorbia ‘Burrows Silver’ (notpatented). ‘Vanilla Swirl’ is distinguishable from ‘Burrows Silver’ byits compact habit, finer foliage, rare flowering, and no reversion togreen.

The first asexual reproduction of ‘Vanilla Swirl’ was accomplished bythe inventor in Dorset, United Kingdom in 1998. The method used wassoftwood cuttings. Since that time subsequent generations have beendetermined stable and true to type.

SUMMARY OF THE INVENTION

The following traits have been repeatedly observed and represent thedistinguishing characteristics of the new Euphorbia cultivar. Thesetraits in combination distinguish ‘Vanilla Swirl’ from all otherexisting varieties of Euphorbia known to the inventor. ‘Vanilla Swirl’has not been tested under all possible conditions and phenotypicdifferences may be observed with variations in environmental, climatic,and cultural conditions, however, without any variance in genotype.

1. Euphorbia ‘Vanilla Swirl’ exhibits a compact rounded growth habit.

2. Euphorbia ‘Vanilla Swirl’ exhibits rare flowering.

3. Euphorbia ‘Vanilla Swirl’ exhibits variegated, fine leaves with greencenters and irregular cream-white margins that are whitest in springturning cream-white in summer.

4. Euphorbia ‘Vanilla Swirl’ exhibits bright red stems in spring fadingto pink by summer.

5. Euphorbia ‘Vanilla Swirl’ exhibits consistently variegated foliagewithout reversion to green.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate the distinguishing traits of thenew Euphorbia cultivar ‘Vanilla Swirl’. The photographs were taken inspring and summer of plants in two-litre containers that were36-month-old and grown out-of-doors in a cultivated area of Dorset,United Kingdom. No chemicals were administered to the plants.

The drawing on sheet 1 illustrates the entire plant in spring from aside perspective.

The drawing on sheet 2 illustrates a close-up view of the white foliagemargins in spring.

The drawing on sheet 3 illustrates the change to cream-white margins insummer.

The drawing on sheet 4 is a close-up view of the flower in spring.Drawings were made using conventional techniques and although flower andfoliage colors may appear different from actual colors due to lightreflectance, they are as accurate as possible by conventionalphotography.

BOTANICAL DESCRIPTION OF THE PLANT

The following is a detailed botanical description of the new Euphorbiacultivar ‘Vanilla Swirl’. Observations, measurements, values andcomparisons were collected in Dorset, United Kingdom from plants thatwere 36 months old and grown out-of-doors in two-litre containers. Colordeterminations are made in accordance with The 1995 Royal HorticulturalSociety Colour Chart from London England, except where general colorterms of ordinary dictionary significance are used. The growingrequirements of the new variety are similar to the species and there areno known growing problems, diseases or pests.

Botanical classification: Euphorbia characias ‘Vanilla Swirl’.

Species: characias.

Common name: Spurge.

Parentage: Euphorbia ‘Vanilla Swirl’ is the naturally occurring self-setseedling that resulted from spontaneous self-hybridization. The parentsare presumed to be the following plants:

Female parent.—Euphorbia characias.

Male parent.—Euphorbia characias.

Propagation method: Softwood cuttings.

Rooting habit: Fibrous and fleshy.

Time to develop roots: In California 2-3 weeks are required for roots todevelop on an initial cutting at 15° Centigrade air temperature.

Crop time: In California 12-16 months are required to develop a finishedtwo-litre container from a rooted cutting.

Growth habit: Compact slow-growing growth habit.

Use: Ornamental landscape plant.

Type: Perennial herb.

Vigor: Low, slow-growing.

Height of plant: 70-90 cm. in height.

Width of plant: 60-90 cm. in width.

Cultural requirements: Plant in three quarters to full sunlight andfree-draining soil.

Diseases and pests: None known to the inventor.

Hardiness: Hardy to minus 8° Centigrade.

Stem:

Branching habit.—Basal branching and upright.

Stem colors.—The stems are blotched with varied colors that range fromthe basic color 68D to a paler pink that is 73D and 66C. The pink basetransitions to brown 172C with green patches that are 145C. Where thestem is obscured by leaves the colors of the stem are 145D and 150D.

Stem shape.—Cylindrical to columnar.

Stem width.—8-11 mm. in width.

Stem length.—28-30 cm. in length.

Stem surface.—The surface area between bundle scars and the surfaceswhere bundle scars are absent is glabrous. Basal surface to mid-stem isheavily covered with bundle scars.

Bundle scars.—Present on stem surface.

Shape of bundle scars.—Linear shaped.

Dimensions of bundle scars.—2-5 mm. in width and 2 mm. in height.

Color of bundle scars.—201D.

Quantity of bundle scars.—Numerous amounting to approximately 42 on a 20cm. long stem.

Other.—Stems exude a white milky sap that can be toxic and may elicitdermal irritation.

Foliage:

Type.—Evergreen.

Leaf arrangement.—Most leaves have spiral arrangement. On the smallerstems some leaves are alternate.

Internode dimensions.—Where leaves are alternate internode is 12 mm. andwhere leaves spiral internode is 1-2 mm.

Leaf division.—Simple.

Leaf shape.—Gladiate.

Mature leaf length.—110 mm. in length.

Mature leaf width.—13 mm. in width.

Young leaf length.—80-90 mm. in length.

Young leaf width.—5-8 mm. in width.

Leaf apex.—Apiculate.

Quantity of leaves.—An average of 250 leaves per branch.

Leaf venation pattern.—Parallel with a prominent central vein.

Margin.—Entire.

Leaf surface (abaxial surface).—Most of the surface area is glabrous butthere is a light amount of pubescence near the central vein.

Leaf surface (adaxial surface).—Most of the surface area is glabrous butthere is a light amount of pubescence near the central vein.

Leaf attachment.—Sessile.

Leaf color in spring (adaxial surface).—The center ranges in green from133A and 133B to 133C while the margin is 155B.

Leaf color in spring (abaxial surface).—The center ranges in green from133A and 133B to 133C while the margin is 155B.

Leaf color in summer (adaxial surface).—The center is 131A and themargin is 158A,B.

Leaf color in summer (abaxial surface).—The center is 131A and themargin is 158A,B.

Other.—There is a milky white fluid that exudes from the leaves if theyare torn or bruised. This substance may illicit dermal irritation.

Flower:

Type.—Inflorescence.

Dimensions of inflorescence.—8-15 mm. in diameter and 5-8 mm. in height.

Inflorescence.—Cyathium.

Flowering season.—Spring.

Flower aspect.—Facing upward and outward.

Peduncle dimensions.—36 mm in length and 2 mm. in width.

Peduncle color.—133A,B.

Peduncle surface.—Glabrous.

Petals.—Apetalous.

Sepals.—Apetalous.

Floral leaf attachment.—Connate perfoliate.

Dimensions of floral leaves.—12 mm. in length and 2 cm. in width.

Shape of floral leaf.—Reniform.

Color of floral leaf.—Center is 133A,B,C and margins are 158C,D.

Number of floral leaves.—Two in number.

Fused or unfused.—Basally fused.

Number of cyathium.—Two cupped within the center of two basally fusedfloral leaves.

Margins.—Entire.

Shape of cyathium.—Cupulate.

Number of floral leaves on each cyathium.—Two.

Fused or unfused.—Basally fused.

Color of cyathium.—Mostly 155D with a splash of green 133A and 133C inthe center.

Dimensions of cyathium.—5-8 mm. in length and 8-15 mm. in diameter.

Flower fragrance.—Absent.

Bud shape.—Globose.

Bud dimensions.—4-6 mm. in diameter and 3-5 mm. in length.

Bud color.—155D.

Reproductive organs:

Stamen color.—155C.

Stamen dimensions.—Less than 0.50 mm. in length and 1 mm. in diameter.

Anther shape.—Ovoid.

Anther color.—155C.

Anther dimensions.—1 mm. in width and 2 mm. in length.

Pollen.—Minimal amount.

Ovary.—None observed.

Color of pistil.—155C.

Style color.—155C.

Stigma color.—155C.

Dimensions of stigma.—Less than 0.75 mm. in width and less than 0.75 mm.in height.

Seed: No seed has been observed. The plant is presumed to be sterile.

I claim:
 1. A new and distinct cultivar of Euphorbia plant named‘Vanilla Swirl’ as described and illustrated.